Pressure reducing valve with an integral venturi

ABSTRACT

A pressure reducing valve includes a valve housing, plunger, pressure sensing cavity, and biasing member. The valve housing includes a valve inlet and valve outlet in selective fluid communication with each other. The plunger is in the valve housing and movable between a closed position and open position. The plunger is positioned downstream from the valve inlet and upstream from the valve outlet. The plunger includes a venturi and a channel. The venturi is within the plunger and has a venturi inlet and venturi outlet. The channel is within the plunger and is in fluid communication with the venturi. The pressure sensing cavity is in fluid communication with the channel. The biasing member exerts a biasing force on the plunger toward the open position. The channel is in fluid communication with the pressure sensing cavity to provide a fluid pressure that is lower than the outlet pressure during flow.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 16/851,540, filed on Apr. 17, 2020, which claims priority toU.S. Provisional Patent Application No. 62/843,165 filed on May 3, 2019,the entire contents of which are incorporated by reference herein.

FIELD

This application relates to pressure reducing valves.

BACKGROUND

Pressure reducing valves are required in many hydraulic, pneumatic,fuel, and water management systems. Typically, pressure reducing valvesare used to reduce the inlet pressure to a set output fluid pressure.For example, the inlet fluid pressure of 100 pounds per square inch(“psi”) is set to a reduced outlet fluid pressure of 65 psi. In mostcases, the pressure reducing valve operates as a balance of forces onthe sealing component (for example, a piston or a diaphragm), where acompressive force of a spring can be used to set the outlet fluidpressure. The additional forces involved in the force balance caninclude the outlet fluid pressure. In some cases, changing thecompressive force of the spring can adjust the set outlet fluidpressure.

Current pressure reducing valves often experience a deviation from theset outlet fluid pressure. For example, as downstream demand or anoutlet flow rate increases (for example, via opening of additionalfaucets), the sealing component of the pressure reducing valve opens inresponse. Correspondingly, the additional opening of the pressurereducing valve imposes a proportional decrease in outlet fluid pressureknown as fall off pressure, which is the difference between thedownstream set static pressure and the flowing water pressure.

SUMMARY

Conventional pressure reducing valves have no way to compensate forchanges in outlet fluid pressure, due to fluctuations in outlet fluidflow rate (e.g., increases in downstream demand). Other pressurereducing valve configurations contemplate placing an external venturi atthe outlet side of the pressure reducing valve to provide feedback thatadjusts the amount the pressure reducing valve is open. In such aconstruction, the fluid pressure at a constriction within the venturi istaken and this is used to adjust the degree to which the valve is openwithin the valve housing, via a pipe conduit, in order to alleviate andstabilize the amount of fall-off pressure. Unfortunately, this can leadto a rather bulky system that may not fit an enclosure, where thepressure reducing valve is installed. Further, the pipe conduit itselfand connections between pipe conduit and the valve can be exposed andpotentially damageable, when compared to the valve housing itself, andis thus prone to leaks (e.g., from fractures).

Disclosed herein is an improved pressure reducing valve, which addressesthe above-discussed deficiencies with prior pressure reducing valvedesigns. For example, the disclosed pressure reducing valve includes anintegrally formed venturi and channel within a plunger of the pressurereducing valve. The channel is configured to be in fluid communicationwith a constriction of the venturi and a pressure sensing cavity. Whenthe outlet fluid flow rate fluctuates, the integrally-formed venturi inthe plunger senses this change in outlet fluid flow rate and adjusts aforce imposed on the plunger, effectively eliminating or greatlyreducing any undesirable pressure drops or fall-off. The integration ofthe venturi and channel into the plunger maintains the compact nature ofthe pressure reducing valve. Additionally, the manufacturing of thechannel and venturi within the plunger is relatively simple to fabricateand effectively avoids the exposure of the pipe conduit that would bepresent in an external venturi design. Lastly, the integrated venturiand channel within the plunger significantly decreases the length of therequired channel, when compared to an external venturi with pipe conduitdesign.

According to one aspect, a pressure reducing valve is provided. Thepressure reducing valve includes a valve housing including an inlet inselective fluid communication with an outlet and a plunger positionedbetween the inlet and the outlet in which the plunger is coupled to abiasing member including a diaphragm and/or piston having a pressuresensing cavity. A venturi is integrally formed within the plunger. Theventuri has a venturi inlet and a venturi outlet with a venturiconstriction therebetween. A channel is also integrally formed withinthe plunger with the channel providing fluid communication between theventuri constriction and the pressure sensing cavity. The venturiconstriction is configured to sense and deliver a fluid pressure to thepressure sensing cavity of the biasing member via the channel to adjusta biasing force applied to the plunger by the biasing member.

In some forms of the system, the plunger can include a stem and a headcoupled to the stem. In more specific configurations, the venturi can beintegrally formed within a head of the plunger and the channel can beintegrally formed within a stem of the plunger, with the channel beinggenerally perpendicular relative to the venturi.

In some forms of the system, the biasing member can further include aspring along with a diaphragm and/or piston. Additionally, the stem ofthe plunger can be concentrically positioned relative to the spring,with the spring surrounding (at least in part) the stem of the plunger.

In some forms of the system, a force of the spring and a force of thediaphragm and/or piston are in opposite directions to one another andare summed to establish the biasing force applied to the plunger. Inspecific configurations, the spring may not be within the pressuresensing cavity and the spring and pressure sensing cavity may be axiallystacked relative to one another. To permit adjustment of the reductionof pressure, the pressure reducing valve can include an adjustmentassembly for the biasing member. The adjustment assembly can, forexample, include a bolt or other rotating member and may rotate in afirst direction to axially load the spring and can rotate in a seconddirection to unload the spring. This amount of rotation of the biasingmember can correspond to an outlet fluid pressure of the outlet.

In some forms of the system, the diaphragm and/or piston may besealingly engaged with the plunger, which can define a portion of thepressure sensing cavity.

In some forms of the system, the pressure reducing valve can include aguide positioned within the valve housing. In some cases, the guide caninclude an axial bore that receives the plunger, where the plunger cantranslate within the axial bore of the guide. Additionally, the guidecan include an aperture in selective fluid communication with the axialbore, with the aperture having a smaller radius than the axial bore.

In some forms of the system, the guide can include an opening adjacentto the aperture and on the opposite side of the aperture from the axialbore providing a flow path. Accordingly, the opening can allow selectivefluid communication between the opening and the aperture. It is alsocontemplated that the guide may not have an axial bore, but that theremay be an opening that can be selectively sealed or opened to open orrestrict a flow path through the opening.

In some forms of the system, the head of the plunger can be configuredto engage a surface of the axial bore which can prevent fluidcommunication between the opening and the axial bore. In a more generalsense, the plunger can be used to selectively seal an opening to createor block a flow path through the guide regardless of whether there is anaxial bore or not.

According to another aspect, a method for reducing a fluid pressure lossduring a fluid flow when the fluid flow increases for a system isprovided. The system includes a pressure reducing valve, in which thepressure reducing valve has a housing defining an inlet and an outlet, abiasing member, and a plunger coupled to a diaphragm and/or pistondefining a pressure sensing cavity. The method includes sensing apressure change due to the fluid flow through a venturi integratedwithin the plunger, where the venturi has a venturi constriction. Themethod also includes delivering a fluid pressure of the venturiconstriction to the pressure sensing cavity via a channel and based onthe fluid flow through the venturi, where the channel is in fluidcommunication with the pressure sensing cavity and the venturiconstriction. The channel is also integrated within the plunger. Themethod further includes adjusting a load imposed on the plunger due tothe fluid pressure within the pressure sensing cavity.

In some forms of the method, the plunger can be coupled to the biasingmember which includes the diaphragm and/or piston. In some cases, theload imposed by the biasing member onto the plunger translates theplunger.

In some forms of the method, an increase in the fluid pressure of theventuri constriction translates the plunger thereby decreasing adistance between a head of the plunger and an aperture. The aperture canprovide selective fluid communication between the inlet and the outlet.

In some forms of the method, a decrease in the fluid pressure of theventuri constriction can translate the plunger thereby increasing thedistance between a head of the plunger and an aperture. The aperture canprovide selective fluid communication between the inlet and the outlet.

In some forms of the method, by virtue of the venturi in the plunger,the fluid pressure loss at increased flow rates can be reduced relativea fluid pressure loss in a similar pressure reducing valve but lackingthe venturi in the plunger.

According to still another aspect, a pressure reducing valve isdisclosed. The pressure reducing valve includes a valve housingincluding an inlet in selective fluid communication with an outlet, aplunger coupled to a biasing member including a diaphragm and/or pistonhaving a pressure sensing cavity in which the plunger is positionedbetween the inlet and the outlet, and a low pressure sensing featurewithin the plunger and in communication with the pressure sensingcavity. The low pressure sensing feature is configured to sense anddeliver a fluid pressure to the pressure sensing cavity of the biasingmember and adjust a biasing force applied to the plunger by the biasingmember.

In some forms, the low pressure sensing feature may have an inlet and anoutlet with a low pressure zone therebetween and the pressure reducingvalve further may further include a channel integrally formed within theplunger that provides fluid communication between the low pressure zoneand the pressure sensing cavity. In some forms, the pressure reducingvalve may further include a constriction between the inlet and theoutlet and the low pressure zone may be positioned just after theconstriction and the channel to the pressure sensing cavity maypositioned just after the construction.

In other forms, the various features described above with respect to thefirst aspect of the valve could be employed in this additional aspect ofthe valve, albeit with the venturi being replaced by a low pressuresensing feature more generally.

According to still yet another aspect, a method for reducing a fluidpressure loss during a fluid flow when the fluid flow increases for asystem that includes a pressure reducing valve is disclosed in which thepressure reducing valve includes a housing defining an inlet and anoutlet, a biasing member, a plunger coupled to a diaphragm and/or pistondefining a pressure sensing cavity. A pressure change due to the fluidflow through a low pressure sensing feature integrated within theplunger is sensed. The fluid pressure of the low pressure sensingfeature is delivered to the pressure sensing cavity from the plunger. Aload imposed on the plunger due to the fluid pressure within thepressure sensing cavity is adjusted.

In some forms of the method, the low pressure sensing feature may havean inlet and an outlet with a low pressure zone therebetween and thestep of sensing may detect a pressure change in this low pressure zone.In this arrangement, the pressure reducing valve may further include achannel integrally formed within the plunger in which the channelprovides fluid communication between the low pressure zone and thepressure sensing cavity. There may be a constriction between the inletand the outlet and the low pressure zone can be positioned just afterthe constriction (as the flow path extends from the inlet to the outlet)and the channel to the pressure sensing cavity may be positioned justafter the construction.

In other forms, the various features described above with respect to thefirst aspect of the method could be employed in this additional aspectof the method, albeit with the venturi being replaced by a low pressuresensing feature more generally.

These and still other advantages of the invention will be apparent fromthe detailed description and drawings. What follows is merely adescription of some preferred embodiments of the present invention. Toassess the full scope of the invention, the claims should be looked to,as these preferred embodiments are not intended to be the onlyembodiments within the scope of the claims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a pressure reducing valve.

FIG. 2 is an exploded perspective view of the pressure reducing valve ofFIG. 1 .

FIG. 3 is a cross-sectional elevation view of the pressure reducingvalve of FIG. 1 taken along line 3-3, shown in a closed position.

FIG. 4 is a cross-sectional elevation view of the pressure reducingvalve of FIG. 3 , shown in an open position with darker arrowsindicating fluid flow.

FIG. 5 is a cross-sectional plan view of the pressure reducing valve ofFIG. 1 , taken along line 5-5 of FIG. 4 and shown in an open position.

FIG. 6 is a perspective view of another pressure reducing valve.

FIG. 7 is an exploded perspective view of the pressure reducing valve ofFIG. 6

FIG. 8 is a cross-sectional elevation view of the pressure reducingvalve of FIG. 6 taken along line 8-8 of FIG. 6 and shown in a closedposition.

FIG. 9 is a graph of the downstream pressure verses the flow rate forboth a typical pressure reducing valve and an embodiment of the pressurereducing valve of the present disclosure.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

As used herein, unless otherwise limited or defined, discussion ofparticular directions is provided by example only, with regard toparticular embodiments or relevant illustrations. For example,discussion of “top,” “front,” or “back” features is generally intendedas a description only of the orientation of such features relative to areference frame of a particular example or illustration.Correspondingly, for example, a “top” feature may sometimes be disposedbelow a “bottom” feature (and so on), in some arrangements orembodiments.

The following discussion is presented to enable a person skilled in theart to make and use embodiments of the invention. Various modificationsto the illustrated embodiments will be readily apparent to those skilledin the art, and the generic principles herein can be applied to otherembodiments and applications without departing from embodiments of theinvention. Thus, embodiments of the invention are not intended to belimited to embodiments shown, but are to be accorded the widest scopeconsistent with the principles and features disclosed herein. Thefollowing detailed description is to be read with reference to thefigures, in which like elements in different figures have like referencenumerals. The figures, which are not necessarily to scale, depictselected embodiments and are not intended to limit the scope ofembodiments of the invention. Skilled artisans will recognize theexamples provided herein have many useful alternatives and fall withinthe scope of embodiments of the invention.

As used herein, unless otherwise specified or limited, “at least one ofA, B, and C,” and similar phrases, are meant to indicate A, or B, or C,or any combination of A, B, and/or C. As such, this phrase, and similarother phrases can include single or multiple instances of A, B, and/orC, and, in the case that any of A, B, and/or C indicates a category ofelements, single or multiple instances of any of the elements of thecategories A, B, and/or C.

As illustrated in FIG. 1 , a pressure reducing valve 10 includes a valvehousing 12 that defines an inlet 14 and an outlet 16. The pressurereducing valve 10 is installed such that the inlet 14 receives a highpressurized fluid and the outlet 16 expels the fluid at a particular,reduced fluid pressure when fluid is flowing through the valve 10. Thepressure reducing valve 10 also includes an adjustment assembly 18received within an adjustment assembly housing 20, which is coupled tothe valve housing 12. In some embodiments, and as illustrated, theadjustment assembly housing 20 is secured to the valve housing 12 bythreaded engagement. Additionally or alternatively, the valve housing 12can be made of various suitable materials (e.g., metals) thatsufficiently withstand the various forces of the pressurized fluid.

Turning now to FIG. 2 , the various internal components of the pressurereducing valve 10 are separately shown exploded apart from one anotherso that the figures that follow and functionality can be betterunderstood. The pressure reducing valve 10 includes a guide 22positioned within the valve housing 12 and having retaining walls 24, 26that downwardly protrude from a generally central guide body 28, wherethe retaining walls 24, 26 define an axial bore 30 centrally therewithin. However, it is also contemplated that there need not beretaining walls, and the “axial bore” could effectively be an open spacein which a plunger is positioned or there could be fewer retaining wallsthan those illustrated (e.g., wall 26 could be eliminated). Withadditional reference being made to FIG. 5 , the guide 22 also includesupwardly protruding supports 32, 34, 36, 38 that are spaced apartradially and are integrally formed with a ring 40. The positioning ofthe supports 32, 34, 36, 38 on the ring 40 define openings 42, 44, 46,48 (most clearly identified in FIG. 5 and are generally radiallyextending) which are specifically defined by two adjacent ones of thesupports 32, 34, 36, 38. For example, the supports 32, 34 define theopening 42, the supports 34, 36 define the opening 44, the supports 36,38 define the opening 46, and the supports 38, 32 define the opening 48.The ring 40 also includes an axially-extending channel 52 that extendsthrough the entirety of the ring 40 and beyond a bottom surface 54 ofthe ring 40, via a flange 56 protruding from the bottom surface 54. Theguide 22 also includes a circular aperture 50 (see FIG. 5 ) that extendsthrough the entirety of the guide body 28.

With reference being made to FIGS. 2 and 3 , the pressure reducing valve10 also includes a plunger 58 having a stem 60 and a head 62. The stem60 and the head 62 are coupled by threaded engagement thereby securingthem together. In some embodiments, the stem 60 and the head 62 can befixed together by other methods known in the art. The head 62 of theplunger 58 includes a gasket 64 that is placed within a bore or upwardlyfacing channel on a surface of the head 62 for selectively forming aseal with the guide 22 when the plunger 58 is in the closed position ofFIG. 3 .

As best illustrated in FIGS. 3 and 4 , the plunger 58 is axiallyreceived within the guide 22. Specifically, the stem 60 of the plunger58 is received within the channel 52 extending through the ring 40,whereas the head 62 is received within the axial bore 30 defined by theretaining wall(s) 24, 26. This allows the stem 60 of the plunger 58 totranslate within the channel 52. Similarly, the head 62 of the plunger58 translates within the axial bore 30. As illustrated in FIGS. 2-5 ,the head 62 of the plunger 58 has a radius larger than the circularaperture 50, thus the head 62 of the plunger 58 can only translatewithin the axial bore 30 until the head 62 of the plunger 58 contactsthe guide body 28. As previously noted, the gasket 64 is situated on thehead 62 and sealingly engages with the lower side of the guide body 28when the head 62 of the plunger 58 contacts the guide body 28, thusproviding a fluid-tight seal. In some embodiments, and as illustrated,the stem 60 of the plunger 58 also includes a gasket 86 that creates asliding seal between the stem 60 of the plunger 58 and a portion of theguide 22. This seal can prevent fluid from the valve from entering thepressure sensing cavity which will now be further described.

The pressure reducing valve 10 includes a diaphragm 66 that iscompressed between the periphery of the ring 40 and the adjustmentassembly housing 20 and which further centrally receives a portion ofthe stem 60 of the plunger 58. The coupling of the diaphragm 66 with thering 40 and the plunger 58 defines a pressure sensing cavity 68, as isbest illustrated in FIGS. 3 and 4 .

While a diaphragm is found in the illustrated embodiment, it iscontemplated that a piston could be used in place of a diaphragm tosimilar effect with the piston defining one part of a pressure sensingcavity of variable volume. So while a diaphragm is described herein, itwill be readily appreciated that such a diaphragm could be replaced witha sliding piston member in other mechanical configurations andarrangements.

Situated above the valve housing 12 and the pressure sensing cavity 68is the adjustment assembly 18. The adjustment assembly 18 includes abiasing member 70 received within the adjustment assembly housing 20 andconfigured to impose a downward biasing force onto the diaphragm 66(and/or a piston if a piston is present) and the plunger 58. In someembodiments, the biasing member 70 can be a spring as illustrated.

The adjustment assembly 18 also includes retainers 72, 74 eachpositioned on an axial end of the biasing member 70, configured toprevent movement of the biasing member 70 and accommodate itscompression and expansion. The retainer 72 includes a central aperture76 configured to receive a threaded portion of the stem 60 of theplunger 58 therethrough. A nut 78 engages with the threaded portion ofthe stem 60 of the plunger 58 to secure the retainer 72 to the plunger58. The retainer 72 includes a first side having circumferentiallyprotruding edges that prevent movement of the biasing member 70, when anend of the biasing member 70 engages the first side of the retainer 72.Opposite the first side of the retainer 72 is a second side that engagesthe diaphragm 66. However, as noted above, the diaphragm 66 and pressuresensing cavity could also involve a piston instead of or in addition tothe diaphragm 66.

The adjustment assembly 18 also includes nuts 80, 82 that threadinglyengage a bolt 84. The nut 80 is received within the adjustment assemblyhousing 20. The nut 82 is located exteriorly, relative to the adjustmentassembly housing 20, and engages an exterior surface of the adjustmentassembly housing 20. Rotation of the bolt 84 in a first directiondownwardly translates the retainer 74, which compresses the biasingmember 70 and imparts a downward force on the retainer 72. The downwardforce on the retainer 72 then imposes a downward force on the plunger 58and the diaphragm 66 (and/or piston, as applicable in some designs).This downward force on the plunger 58, along with other forces discussedbelow, can be used to set or adjust the desired outlet pressure of thepressure reducing valve 10. Conversely, rotation of the bolt 84 in asecond direction decompresses the biasing member 70, via the upwardtranslation of the retainer 74, thus reducing the downward forces on thecomponents discussed above.

As shown in FIG. 3 , the pressure reducing valve 10 is fully assembledand in a closed configuration. As discussed above, rotation of the bolt84 in the first direction imposes a compressive force on the plunger 58(e.g., via the biasing member 70), which can set the outlet pressure ofthe pressure reducing valve 10. However, other forces also determinewhether the head 62 of the plunger 58 contacts the guide 22 to seal theinlet 14 from the outlet 16 so the valve 10 remains closed or whetherthe head 62 of the plunger 58 separates from the guide 22 to place theinlet 14 and the outlet 16 in fluid communication with one another suchthat the valve 10 is open and, if the valve 10 is open, the outletpressure of the pressure reducing valve 10. These other forces includethe inlet fluid pressure, the outlet fluid pressure, the force requiredto unseat the plunger 58, and the pressure within the pressure sensingcavity 68. These forces are imposed on the plunger 58 and determinewhether the plunger will be seated, unseated, or positioned at anintermediate position based on a biasing force. In the closedconfiguration of the pressure reducing valve 10 in FIG. 3 , the head 62of the plunger 58 contacts the guide 22 to seal the inlet 14 from theoutlet 16. The valve 10 remains in this condition unless the biasingforce is great enough to overcome the force required to unseat theplunger which requires overcoming the pressure within the pressuresensing cavity 68.

As illustrated in FIG. 3 , the pressure sensing cavity 68 is in fluidcommunication with a venturi 88 via a channel 90 which are both part ofthe plunger 58. Specifically, the channel 90 provides fluidcommunication between the pressure sensing cavity 68 and a venturiconstriction 92 of the venturi 88. As illustrated, the venturi 88 isintegrated within the head 62 of the plunger 58 and the channel 90 isintegrated within the stem 60 and the head 62. The venturi 88 alsoincludes a venturi inlet 94 and a venturi outlet end 96. The venturiinlet 94 decreases in cross-sectional area, tapering toward the venturiconstriction 92. In some embodiments, and as illustrated, the venturiinlet 94 includes a funnel portion 98 that increases the cross-sectionalarea of the inlet 94 of the venturi 88. This can allow the venturi 88 tobetter receive a fluid flow from the inlet 14. Similarly to the venturiinlet 94, the venturi outlet 96 decreases in cross-sectional area,tapering toward the venturi constriction 92. However, in someembodiments, the change in cross-sectional area can vary, as well as thespecific cross-sections of the venturi inlet and outlet 94, 96.

In some embodiments, and as illustrated, the channel 90 has a first endthat is coupled perpendicularly to the venturi constriction 92. Thechannel 90 has a second end opposite and perpendicular to the first end,which is in fluid communication with the pressure sensing cavity 68. Asbest illustrated in FIGS. 3 and 4 , the channel 90 extends in a straightmanner from the first end until abruptly changing orientationsperpendicularly, defining an “L-shape” of the channel 90. Although thechannel 90 is generally an L-shape as illustrated, other configurationsare possible. For example, in some embodiments, the second end of thechannel 90 can be angled obliquely relative the straight first end ofthe channel 90. Still other embodiments include one continuous curvedchannel 90.

FIG. 4 illustrates the pressure reducing valve 10 in an open state inwhich when the plunger 58 is unseated because the spring force issufficient to open the valve 10 by displacing the plunger 58 against thecollective biasing force of the pressure sensing cavity 68. When thepressure reducing valve 10 is in an open configuration (shown in bothFIGS. 4 and 5 ), fluid can flow through the valve 10. Following thearrows in FIGS. 4 and 5 , a fluid is received at the inlet 14 of thevalve housing 12 at a specific inlet fluid pressure and having aspecific inlet flow rate. The fluid flows from the inlet 14, through theopenings 42, 44, 46, 48 of the guide 22, and then down (down, at leastrelative to the orientation of FIG. 4 ) through the circular aperture 50of the guide body 28. Then, a portion of the fluid flow 100 flows intothe fluid conduit 102, allowing the portion of fluid flow 100 to flowinto and through the venturi 88, via the venturi inlet 94. Anotherportion of the fluid flow 104, flows around the head 62 of the plunger58. Both the portions of fluid flow 100, 104 converge and are expelledvia the outlet 16.

Referring specifically to FIG. 5 , the cross-sectional view taken atline 5-5 of FIG. 4 , further helps to illustrate the fluid flow paththrough the pressure reducing valve 10, when the pressure reducing valve10 is in an open position. The flow passes between the supports 32, 34,36, 38 of the guide 22 with the fluid flow, designated by number 106,flowing through the inlet 14 and through the openings 42, 44, 46, 48 anddown the aperture 50 of the guide 22. A wall 108 of the valve housing 12prevents the fluid flow 106 from flowing to the outlet 16 other than bythe above-mentioned path. After passing through the aperture 50, thefluid flow 106 then exits to the outlet 16, after flowing around thehead 62 of the plunger 58, or through the venturi 88.

The portion of fluid flow 100 that flows through the venturi 88specifically flows through the venturi constriction 92 and out theventuri outlet end 96. The flow within the venturi 88 and through theventuri constriction 92 is converted into a decreased fluid pressure (inrelation to the outlet pressure) that is delivered to the pressuresensing cavity 68 via interconnecting channel 90. Thus, the venturiconstriction 92 allows for a pressure delivered to the plunger 58 (viathe pressure sensing cavity 68) to be dependent, at least in part, on anoutlet flow rate of the outlet 16 with the rest of the force beingapplied by the biasing member/spring 70. This venturi 88 allows for areal-time feedback mechanism to the biasing member 70, which adjusts theplunger 58 in order to better maintain the set outlet fluid pressurecontra to the conventional fall-off pressure that occurs at higher flowrates.

With reference to FIG. 6 , a pressure reducing valve 1010 according toanother embodiment is shown. Many components of the pressure reducingvalve 1010 are similar to those of the pressure reducing valve 10discussed above and have been given a reference numeral that is a valueof one thousand higher than the corresponding similar component in thepressure reducing valve 10 discussed above. For the sake of brevity,only some differences between the pressure reducing valve 10 and thepressure reducing valve 1010 will be discussed below.

As shown in FIG. 6 , the pressure reducing valve 1010 also includes anadjustment assembly 1018 having a nut 1082. In this embodiment, however,the nut 1082 is permanently affixed to or integrally formed with theadjustment assembly housing 1020. As shown in FIG. 8 , thisconfiguration allows for the exclusion of an interior nut (such as thenut 80 discussed above). Instead, the end of the bolt 1084 can directlyengage the retainer 1074.

With reference to FIG. 7 , the guide body 1028 includes only oneretaining wall 1024. This retaining wall 1024 serves as a rail. The head1062 of the plunger 1058 includes two opposing hooks 1110 extendingoutwardly. Each hook 1110 defines a groove to receive a portion of theretaining wall 1024. As such, the retaining wall 1024 is trapped by thehooks 1110, and the head 1062 of the plunger 1058 is constrained totranslate linearly relative to the retaining wall 1024.

The hooks 1110 are disposed on opposite sides of the venturi inlet 1094.The hooks 1110 and the retaining wall 1024 cooperate to form, along withthe funnel portion 1098 of the venturi inlet 1094, the fluid conduit1102. In some embodiments, this bounded fluid conduit 1102 may preventeddies or other turbulent fluid flow characteristics from forming aroundor in the venturi 1088.

Also shown in FIG. 7 , the pressure reducing valve 1010 includes afriction ring 1112 positioned between the diaphragm 1066 and theadjustment assembly housing 1020 such that the diaphragm 1066 does notmove with the adjustment assembly housing 1020. This configuration mayavoid wrinkling or tearing of the diaphragm 1066.

As illustrated in FIG. 8 , the head 1062 of the plunger 1058 includes alow pressure zone 1114 defined therein. In the embodiment shown, the lowpressure zone 1114 is disposed immediately downstream from theconstriction 1092. The channel 1090 is in fluid communication with thislow pressure zone 1114 such that the pressure sensing cavity 1068experiences a fluid pressure that is lower than the fluid pressure atthe valve outlet 1016.

To help illustrate the technical improvement(s) provided by embodimentsdisclosed herein, FIG. 9 illustrates two different “(outlet pressure)versus (outlet flow rate)” curves. A first curve 200 is formed from datataken regarding a typical pressure reducing valve without an integratedventuri. For the first curve 200, as the flow rate increases, the outletpressure correspondingly drops. This increase in flow rate can beattributed to an increase in downstream demand (e.g., opening ofadditional valves, faucets, etc.). Regardless, as the flow rateincreases, the valve opens further to supply the increase in flow rate,but results in a decrease in the outlet fluid pressure in so doing.Thus, there is a relationship between an increase in the outlet flowrate and a decrease in the outlet fluid pressure. A second curve 202 isformed from data taken regarding an embodiment of the pressure reducingvalve with an integrated venturi of the present disclosure. Asillustrated in FIG. 9 , the second curve 202 is roughly horizontal asthe outlet fluid pressure is constant. This is the case because, as theflow rate increases, the venturi 88, 1088 supplies a pressure to thediaphragm 66, 1066 (and/or piston) which alters the biasing force andhelps to maintain the set outlet pressure. Particularly, as the flowrate increases, the venturi 88, 1088 supplies a reduced pressure to thepressure sensing cavity 68, 1068.

Thus, referring to FIGS. 1-8 collectively, the pressure feedback of thepressure reducing valve 10, 1010 can be more easily understood. For thepressure reducing valve 10, 1010 in an open configuration, the fluidflow pathways have already been discussed. However, suppose thedownstream flow rate increases (e.g., via opening of additional valves,faucets, etc.). In this case, the increase in fluid flow is received bythe venturi 88, 1088, and specifically the venturi constriction 92,1092. The venturi constriction 92, 1092 decreases the delivered pressureto the pressure sensing cavity 68, 1068 as the fluid flow has increased,corresponding to the venturi effect. This decrease in pressure withinthe pressure sensing cavity 68, 1068 imparts a lesser upward force onthe plunger 58, 1058 and correspondingly opens the valve 10, 1010further (e.g., due to the downward biasing force by the biasing member70, 1070). So, as the outlet fluid flow increases, there exists aninherent pressure drop, but the venturi constriction 92, 1092 imparts acounteracting decrease in pressure based on the outlet fluid flow,essentially canceling at least a portion of the decreased change inoutlet fluid pressure.

Conversely, the pressure reducing valve 10, 1010 can also compensate forincreases in outlet pressure. For example, suppose that the outlet fluidpressure increases proportionally to the outlet flow rate (e.g., via adecrease in outlet flow rate due to closing of additional valves,faucets, etc.). The decrease in outlet flow rate is sensed by theventuri 88, 1088 and specifically the venturi constriction 92, 1092. Theventuri constriction 92, 1092 increases the delivered venturi pressureto the pressure sensing cavity 68, 1068, imparting a greater upwardforce on the plunger 58, 1058 and correspondingly closing the valve 10,1010 further. So, as the outlet fluid flow decreases, there exists aninherent pressure drop, but the venturi constriction 92, 1092 imparts acounteracting increase in pressure based on the outlet fluid flow,essentially canceling at least a portion of the change in outlet fluidpressure.

It will be noted that, while a pressure reducing valve 10, 1010 with aventuri 88, 1088 in the plunger 58, 1058 has been illustrated, it iscontemplated that other low pressure features (other than a venturi) canalso be used or placed to similar effect in the plunger 58, 1058. Forexample, it is contemplated that in place of the illustrated venturi 88,1088, there could be a low pressure zone produced with one or moreobstructions or the like. As another example, it is also contemplatedthat in place of the illustrated venturi 88, 1088, there could be ahydrodynamic foil directing high speed flow between a narrow gap betweentwo plates. Additionally, rather than using a conventional venturiconstruction, it is contemplated that other flow patterns may beemployed. Further, one or more sensors may be located within the plunger58, 1058 that detects low pressure conditions and converts this to anadjustment in the biasing force applied to the plunger 58, 1058 in adigital manner utilizing a controller.

It should be appreciated that various other modifications and variationsto the preferred embodiments can be made within the spirit and scope ofthe invention. Therefore, the invention should not be limited to thedescribed embodiments. To ascertain the full scope of the invention, thefollowing claims should be referenced.

What is claimed is:
 1. A pressure reducing valve, the pressure reducingvalve comprising: a valve housing including an inlet in selective fluidcommunication with an outlet; a plunger coupled to a biasing memberincluding a diaphragm and/or piston having a pressure sensing cavity,the plunger positioned between the inlet and the outlet; a venturiintegrally formed within the plunger, the venturi having a venturi inletend and a venturi outlet end with a venturi constriction therebetween; achannel integrally formed within the plunger, the channel providingfluid communication between the venturi constriction and the pressuresensing cavity; and wherein the venturi constriction is configured tosense and deliver a fluid pressure to the pressure sensing cavity of thebiasing member via the channel to adjust a biasing force applied to theplunger by the biasing member.
 2. The pressure reducing valve of claim1, wherein the plunger includes a stem end and a head end opposite thestem end.
 3. The pressure reducing valve of claim 2, wherein the venturiis integrally formed within a head at the head end of the plunger. 4.The pressure reducing valve of claim 3, wherein the channel isintegrally formed within a stem of the plunger and is perpendicularrelative to the venturi.
 5. The pressure reducing valve of claim 2,wherein the biasing member further includes a spring, wherein a stem endof the plunger is concentrically positioned relative the spring, andwherein the spring surrounds the stem end of the plunger.
 6. Thepressure reducing valve of claim 1, wherein the biasing member furtherincludes a spring and in which a force of the spring and a force of thediaphragm and/or piston are in opposite directions to one another andare summed to establish the biasing force applied to the plunger.
 7. Thepressure reducing valve of claim 6, wherein the spring is not within thepressure sensing cavity.
 8. The pressure reducing valve of claim 6,further comprising an adjustment mechanism for the biasing member, theadjustment mechanism being configured to rotate in a first direction toload the spring and to rotate in a second direction to unload thespring.
 9. The pressure reducing valve of claim 8, wherein an amount ofrotation of the biasing member corresponds to an outlet fluid pressureof the outlet.
 10. The pressure reducing valve of claim 1, wherein thediaphragm and/or piston is sealingly engaged with the plunger to definea portion of the pressure sensing cavity.
 11. The pressure reducingvalve of claim 1, further including a guide member positioned within thevalve housing.
 12. The pressure reducing valve of claim 11, wherein theguide member includes an axial bore that receives the plunger; andwherein the plunger translates within the axial bore of the guidemember.
 13. The pressure reducing valve of claim 12, wherein the guidemember further includes an aperture in selective fluid communicationwith the axial bore; and wherein the aperture has a smaller radius thanthe axial bore.
 14. The pressure reducing valve of claim 13, wherein theguide member further includes an opening adjacent to the aperture and onthe opposite side of the aperture from the axial bore, the openingallowing selective fluid communication between the opening and theaperture.
 15. The pressure reducing valve of claim 14, wherein the headend of the plunger is configured to engage a surface of the axial bore,thereby preventing fluid communication between the opening and the axialbore.